1. Field of the Invention
The present invention relates generally to closing percutaneous punctures, and more particularly to a self-locking closure device for sealing percutaneous punctures.
2. Related Art
U.S. Pat. No. 5,282,827 (hereinafter, the '827 patent), entitled Hemostatic Puncture Closure System and Method of Use, teaches systems for sealing a percutaneous incision or puncture in a blood vessel. The systems of the '827 patent comprise a closure device, an introducer, and a deployment instrument including a carrier for the closure device. The closure device has three basic components, namely, a sealing member, an intra-arterial anchor, and a positioning member. The sealing member is in the form of an elongated rod-like plug, e.g., a compressed hemostatic, resorbable collagen sponge or foam. This plug member is arranged for sealing the puncture. The anchor is an elongated, stiff, low-profile member which is arranged to be seated inside the artery against the artery wall contiguous with the puncture. The anchor is molded of non-hemostatic resorbable polymer similar to resorbable suture. The positioning member comprises a filament, e.g., a resorbable suture. The filament connects the anchor and the collagen plug (sealing member) in a pulley-like arrangement, and includes a portion extending outside the patient's body. The outwardly located filament portion is arranged to be pulled, i.e., tension applied thereto, after the anchor is located within the interior of the artery and in engagement with the inner wall of the artery contiguous with the incision or puncture. The pulling on the filament causes its pulley arrangement to move the plug in the puncture tract toward the anchor. A tamper forming a portion of the deployment instrument is slid down the filament while the filament is maintained in tension to gently tamp the plug in the puncture tract to cause the plug to deform so that its diameter increases. Tension is maintained on the filament by use of an externally located spring during the tamping procedure. The expansion of the plug within the tract is enhanced by the fact that it is formed of a compressed collagen so that it expands in the presence of blood within the puncture tract. The expansion of the plug within the puncture tract serves to hold it in place. Moreover, the closure device quickly becomes locked in place through the clotting of the hemostatic collagen plug within the puncture tract. The spring serves to hold the plug in its deformed state until such time that the plug is locked in place by the hemostatic clotting action. Once this has occurred, so that the plug is effectively locked within the puncture tract, the externally located spring can be removed. This typically occurs after approximately 30 minutes. After the spring is removed, the filament is severed at the top of the tamper. The tamper is then removed and the remaining portion of the filament is cut subcutaneously prior to the discharge of the patient. The portion of the filament connecting the anchor to the plug remains in tension, thereby holding the closure device permanently in place until it is eventually absorbed by the patient's body.
U.S. Pat. No. 5,662,681 (hereinafter, the '681 patent), entitled Self-locking Closure for Sealing Percutaneous Punctures, also teaches systems for sealing a percutaneous incision or puncture in a blood vessel.